Figures

In protocol 1, concentrations in the C3 and C7.1* fraction were compared. Because C7.1 was pipetted into a different vial, the C3 fraction was also pipetted into another vial (before freezing) to eliminate possible effects due to tube adsorption on only the C7.1 fraction. C, cerebrospinal fluid fraction; RT, room temperature; liq, liquid; f/t, freeze–thaw cycle. The boxes explain the goals of the different protocols.

Fig. 3.Relative median differences (%) between the different freezing conditions and introductions of a delay before freezing, compared with freezing at −80 °C.

Results are presented as the relative median difference with 95% CI. For example, the relative median difference for Aβ1–42 comparing samples that remained at room temperature (RT) for 48 h and samples that were frozen immediately at −80 °C is approximately 8%, indicating that the Aβ1–42 concentrations are 8% higher in samples that were kept at room temperature for 48 h.